Where a multi-storied building incorporates an elevator or lift, the elevator typically constitutes the most mechanically complicated and most expensive component of the building. Construction budgets for multiple storied residential homes have historically been more restricted than construction budgets of multiple storied commercial buildings. Accordingly, elevators have historically been less commonly installed within multiple storied homes than multiple storied commercial buildings. Where an elevator is installed within a commercial building, mechanical components such as the elevator's door assembly commonly comprises a superior, though mechanically complex and typically expensive, telescoping pocket door assembly. In contrast, where an elevator is installed within a multiple story residential home, such elevator's door assembly commonly comprises functionality inferior scissor bar gates or swinging doors chosen as a result of such typically reduced construction budget. The different economies of commercial versus home construction has historically relatively compromised the functionality of home elevator door assemblies in pursuit of lower cost.
The typically small size of residential elevator shafts and elevator cabs has historically further driven such compromises against functionality in home elevators. Wall spaces and elevator shaft spaces which are typically available within a common multi-storied residential home will often fail to accommodate types of functionally superior elevator doors which are commonly installed within a commercial building. For example, an elevator door assembly for a small elevator in a commercial building commonly comprises single sliding or pocket door panels which, in their opened positions, overlap portions of a wall of the cab or a wall of the elevator shaft. In contrast, cab wall and shaft wall spaces of a home elevator often fail to accommodate such overlapped positioning of such door panels. Accordingly, both the typical physical dimensions of homes and home construction economies have historically undesirably militated against the incorporation of functionally superior telescoping elevator door panel assemblies.
The instant invention solves or ameliorates problems discussed above by providing a telescoping elevator door assembly which achieves mechanical and cost economies through the provision of ladder frame roller track and header beam assemblies wherein the ladder frame incorporates a plurality of substantially identical and laterally co-extensive roller tracks.